Medical Cell Biology Commons^™

Haploidentical Hematopoietic Stem Cell Transplantation: Rationale, Development, And Jefferson’S Method, Susan Mcilvaine, Dolores Grosso, Rn, Crnp, Dnp, Beth Colombe

Department of Pathology Honors Program Student Research Symposium

INTRODUCTION

There are many indications for hematopoietic stem cell transplantation. In addition to hematologic malignancies, transplants are performed in certain non-hematologic malignancies, for marrow disorders such as Sickle Cell Anemia, and for various inherited disorders such as SCID. Traditionally, transplants have been performed between donors and recipients that are a complete HLA match (typically matched siblings). That is, patients have identical HLA alleles on both copies of chromosome 6. HLA alleles code for major histocompatibility complex molecules, which are the proteins that cause transplant rejection when a mismatch between donor and recipient is present. Thus, matched transplants have been historically …

Small Cell Carcinoma Of The Bladder: A Rare Entity, Andrew H. Matthews, Ruth Birbe, Md

Department of Pathology Honors Program Student Research Symposium

BACKGROUND

Primary small cell carcinoma of the urinary bladder is a rare tumor, accounting for less than 1% of the annual 70,000 cases of urinary bladder cancer.¹ Accordingly, little data is available beyond case series to guide diagnosis or treatment. Overall prognosis remains poor with five year survival often markedly below 50%. Current staging and treatment remains largely based on extrapolation from small cell carcinoma of the lung. We review two recent cases of bladder small cell carcinoma with a focus on comparing and contrasting with lung small carcinoma.

Giant Cell Tumor Of Soft Tissue: A Case Study, Rachel Schneider, Brian J. O'Hara

Department of Pathology Honors Program Student Research Symposium

BACKGROUND

Giant cell tumors of soft tissue are relatively uncommon tumors. They are considered to be the soft tissue counterpart to giant cell tumors of bone. Both tumors consist of multi-nucleated giant cells evenly distributed throughout a background of epithelioid mononuclear cells, and are usually benign, but can be locally invasive. Giant cell tumors of soft tissue typically occur in patients over age 40, and show no gender or racial predilection. They present as firm, well demarcated masses, which are not connected to the underlying muscle, tendon, or bone. Giant cell tumors of soft tissue are generally small, and tend …

Small Cell Carcinoma Of The Breast, Victor Carlson, Paolo Cotzia, Md, Juan P. Palazzo, Md

Department of Pathology Honors Program Student Research Symposium

INTRODUCTION

Small cell carcinoma of the breast (SCCB) is a rare, highly aggressive neoplasm first reported in 1983. With striking histologic similarity to small cell carcinoma of the lung, it is comprised of small cells with relatively large, hyperchromatic nuclei and scanty cytoplasm. While capable of hormone secretion, this is a rare occurrence in this variant of small cell carcinoma. Patients typically present with a suspicious breast mass confirmed on imaging, with variable lymph node invasion.

Fibrosing Cholestatic Hepatitis C Post-Liver Transplantation: A Case Study, Layla Hatem, Wei Jiang, Md, Phd

Department of Pathology Honors Program Student Research Symposium

Introduction:

Liver Transplantation:

• Hepatitis C infection is the most common indication for liver transplantation in the US
• HCV infection of the liver allograft occurs within hours from circulating virions.

-Serum RNA levels are observed in the first several weeks.

-Acute hepatitis occurs in 2-6 months

-Chronic hepatitis occurs in 3-9 months

***Persistence of HCV infection is the rule after transplantation due to immune suppression

Chronic recurrent HCV infection post transplantation

• There are four distinct patterns of recurrent chronic HCV in the liver allograft.

-Usual chronic HCV (>70%)

-Fibrosing Cholestatic Hepatitis C (5-10%)

-Plasma cell-rich HCV

-HCV overlapping with rejection …

Bcl2 Expression And Bcl2/Myc Dual Expression Predicts Inferior Survival In Primary Central Nervous System Lymphoma, Guldeep Uppal, Md, Zi-Xuan (Zoe) Wang, Phd, Renu Bajaj, Phd, Mark T. Curtis, Md, Phd, Charalambos C. Solomides, Md, Jon Glass, Md, Peter M. Banks, Stephen C. Peiper, Md, Jerald Z. Gong, Md

Department of Pathology, Anatomy, and Cell Biology Resident's Posters

Background

Primary CNS lymphoma (PCNSL) is a rare type of diffuse large B-cell lymphoma (DLBCL) arising from and usually confined to CNS. Understating of the pathogenesis and prognostic markers is a challenge due to rarity of this neoplasm and paucity of the material available to study. Recent studies have shown that dual expression of MYC and BCL2 in DLBCL contributes to inferior overall survival. The prognostic value of MYC and BCL2 in PCNSL is not well studied.

Inputs Drive Cell Phenotype Variability., James Park, Anthony Brureau, Kate Kernan, Alexandria Starks, Sonali Gulati, Babatunde Ogunnaike, James S. Schwaber, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

What is the significance of the extensive variability observed in individual members of a single-cell phenotype? This question is particularly relevant to the highly differentiated organization of the brain. In this study, for the first time, we analyze the in vivo variability within a neuronal phenotype in terms of input type. We developed a large-scale gene-expression data set from several hundred single brainstem neurons selected on the basis of their specific synaptic input types. The results show a surprising organizational structure in which neuronal variability aligned with input type along a continuum of sub-phenotypes and corresponding gene regulatory modules. Correlations …

Chronic Arsenic Exposure And Angiogenesis In Human Bronchial Epithelial Cells Via The Ros/Mir-199a-5p/Hif-1Α/Cox-2 Pathway., Jun He, Min Wang, Yue Jiang, Qiudan Chen, Shaohua Xu, Qing Xu, Bing-Hua Jiang, Ling-Zhi Liu

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Background: Environmental and occupational exposure to arsenic is a major public health concern. Although it has been identified as a human carcinogen, the molecular mechanism underlying the arsenic-induced carcinogenesis is not well understood.Objectives: We aimed to determine the role and mechanisms of miRNAs in arsenic-induced tumor angiogenesis and tumor growth.Methods: We utilized an in vitro model in which human lung epithelial BEAS-2B cells were transformed through long-term exposure to arsenic. A human xenograft tumor model was established to assess tumor angiogenesis and tumor growth in vivo. Tube formation assay and chorioallantoic membranes assay were used to assess tumor angiogenesis.Results: We …

A Preliminary Report Of Percutaneous Craniofacial Osteoplasty In A Rat Calvarium, William J. Parkes, Md, Jewel Greywoode, Md, Brian J. O'Hara, Md, Ryan N. Heffelfinger, Md, Howard Krein, Md, Phd

Department of Otolaryngology - Head and Neck Surgery Presentations and Grand Rounds

Objective: To evaluate the potential for injectable, permanent bone augmentation by assessing the biocompatibility and bioactivity of subperiosteal hydroxylapatite (Radiesse) deposition in a rat model.

Methods: Fourteen adult Sprague Dawley rats were injected in the parietal skull with hydroxylapatite (n=10) or a carrier gel control (n=4), using a subperiosteal injection technique on the right and a subcutaneous injection technique on the left. At 1, 3, and 6 months, 3 rats (1 negative control, 2 variables) were sacrificed. At 12 months, the remaining 5 rats were sacrificed. After each harvest, the calvaria were examined under both light and polarized microscopy.

Results: …

Micu1 Controls Both The Threshold And Cooperative Activation Of The Mitochondrial Ca(2+) Uniporter., György Csordás, Tünde Golenár, Erin L Seifert, Kimberli J Kamer, Yasemin Sancak, Fabiana Perocchi, Cynthia Moffat, David Weaver, Sergio De La Fuente Perez, Roman Bogorad, Victor Koteliansky, Jeffrey Adijanto, Vamsi K Mootha, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondrial Ca(2+) uptake via the uniporter is central to cell metabolism, signaling, and survival. Recent studies identified MCU as the uniporter's likely pore and MICU1, an EF-hand protein, as its critical regulator. How this complex decodes dynamic cytoplasmic [Ca(2+)] ([Ca(2+)]c) signals, to tune out small [Ca(2+)]c increases yet permit pulse transmission, remains unknown. We report that loss of MICU1 in mouse liver and cultured cells causes mitochondrial Ca(2+) accumulation during small [Ca(2+)]c elevations but an attenuated response to agonist-induced [Ca(2+)]c pulses. The latter reflects loss of positive cooperativity, likely via the EF-hands. MICU1 faces the intermembrane space and responds to …

Delayed Thrombus Resolution And Fibroproliferative Vascular Wound Healing From Deficiency Of Type Iii Collagen: A Paradoxical Mechanism For Tissue Fragility, Amy J. Reid

Dissertations and Theses (Open Access)

Vascular Ehlers-Danlos syndrome is a heritable disease of connective tissue caused by mutations in COL3A1, conferring a tissue deficiency of type III collagen. Cutaneous wounds heal poorly in these patients, and they are susceptible to spontaneous and catastrophic rupture of expansible hollow organs like the gut, uterus, and medium-sized to large arteries, which leads to premature death. Although the predisposition for organ rupture is often attributed to inherent tissue fragility, investigation of arteries from a haploinsufficient Col3a1 mouse model (Col3a1^+/-) demonstrates that mutant arteries withstand even supraphysiologic pressures comparably to wild-type vessels. We hypothesize that injury …

Different Mechanisms Of Inflammation Induced In Virus And Autoimmune-Mediated Models Of Multiple Sclerosis In C57bl6 Mice., Abhinoy Kishore, Anurag Kanaujia, Soma Nag, A M Rostami, Lawrence C. Kenyon, Kenneth S Shindler, Jayasri Das Sarma

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the human central nervous system (CNS). Neurotropic demyelinating strain of MHV (MHV-A59 or its isogenic recombinant strain RSA59) induces MS-like disease in mice mediated by microglia, along with a small population of T cells. The mechanism of demyelination is at least in part due to microglia-mediated myelin stripping, with some direct axonal injury. Immunization with myelin oligodendrocyte glycoprotein (MOG) induces experimental autoimmune encephalomyelitis (EAE), a mainly CD4(+) T-cell-mediated disease, although CD8(+) T cells may play a significant role in demyelination. It is possible that both autoimmune and nonimmune mechanisms such as …

The Contributions Of Hif-Target Genes To Tumor Growth In Rcc., Ting Zhang, Xiaohua Niu, Lili Liao, Eun-Ah Cho, Haifeng Yang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Somatic mutations or loss of expression of tumor suppressor VHL happen in the vast majority of clear cell Renal Cell Carcinoma, and it's causal for kidney cancer development. Without VHL, constitutively active transcription factor HIF is strongly oncogenic and is essential for tumor growth. However, the contribution of individual HIF-responsive genes to tumor growth is not well understood. In this study we examined the contribution of important HIF-responsive genes such as VEGF, CCND1, ANGPTL4, EGLN3, ENO2, GLUT1 and IGFBP3 to tumor growth in a xenograft model using immune-compromised nude mice. We found that the suppression of VEGF or CCND1 impaired …

Purpose And Criteria For Blood Smear Scan, Blood Smear Examination, And Blood Smear Review., Gene Gulati, Jinming Song, Alina Dulau Florea, Jerald Gong

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

A microscopic examination of an appropriately prepared and well-stained blood smear by a knowledgeable laboratory professional is necessary and clinically useful in a number of circumstances and for a variety of reasons. In this article, an attempt is made to delineate the purpose and criteria for blood smear examination in a variety of circumstances that are encountered in everyday laboratory hematology practice. A blood smear scan serves to at least (a) verify the flagged automated hematology results and (b) determine if a manual differential leukocyte count needs to be performed. Blood smear examination/manual differential leukocyte count with complete blood count …

Rhob Controls Coordination Of Adult Angiogenesis And Lymphangiogenesis Following Injury By Regulating Vezf1-Mediated Transcription., Damien Gerald, Irit Adini, Sharon Shechter, Carole Perruzzi, Joseph Varnau, Benjamin Hopkins, Shiva Kazerounian, Peter Kurschat, Stephanie Blachon, Santosh Khedkar, Mandrita Bagchi, David Sherris, George C Prendergast, Michael Klagsbrun, Heidi Stuhlmann, Alan C Rigby, Janice A Nagy, Laura E Benjamin

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mechanisms governing the distinct temporal dynamics that characterize post-natal angiogenesis and lymphangiogenesis elicited by cutaneous wounds and inflammation remain unclear. RhoB, a stress-induced small GTPase, modulates cellular responses to growth factors, genotoxic stress and neoplastic transformation. Here we show, using RhoB null mice, that loss of RhoB decreases pathological angiogenesis in the ischaemic retina and reduces angiogenesis in response to cutaneous wounding, but enhances lymphangiogenesis following both dermal wounding and inflammatory challenge. We link these unique and opposing roles of RhoB in blood versus lymphatic vasculatures to the RhoB-mediated differential regulation of sprouting and proliferation in primary human blood versus …

The Metastasis Suppressor Kiss1 Lacks Antimetastatic Activity In The C8161.9 Xenograft Model Of Melanoma., Jean-Marc Navenot, Barry Evans, Shinya Oishi, Shohei Setsuda, Nobutaka Fujii, Stephen C Peiper

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The objective of this study was to use the established xenograft model of human melanoma (C8161.9) to test a pharmacological approach to the effect of the metastasis suppressor KISS1. A KISS1 analog was used to inhibit the metastatic development of C8161.9 cells in nude mice. Further experiments were performed to test the validity of the C8161.9 model and test the connection between KISS1 expression and loss of metastatic potential. New clones of C8161.9 cells were obtained, with or without KISS1 expression, and were tested for metastasis formation. The absence of benefit in survival with the KISS1 analog compared with PBS …

Decorin Antagonizes The Angiogenic Network: Concurrent Inhibition Of Met, Hypoxia Inducible Factor 1Α, Vascular Endothelial Growth Factor A, And Induction Of Thrombospondin-1 And Timp3, Thomas Neill, Hannah Painter, Simone Buraschi, Rick T. Owens, Michael P. Lisanti, Liliana Schaefer, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin, a small leucine-rich proteoglycan, inhibits tumor growth by antagonizing multiple receptor tyrosine kinases including EGFR and Met. Here, we investigated decorin during normoxic angiogenic signaling. An angiogenic PCR array revealed a profound decorin-evoked transcriptional inhibition of pro-angiogenic genes, such as HIF1A. Decorin evoked a reduction of hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor A (VEGFA) in MDA-231 breast carcinoma cells expressing constitutively-active HIF-1α. Suppression of Met with decorin or siRNA evoked a similar reduction of VEGFA by attenuating downstream β-catenin signaling. These data establish a noncanonical role for β-catenin in regulating VEGFA expression. We found that exogenous …

Mir-145 Directly Targets P70s6k1 In Cancer Cells To Inhibit Tumor Growth And Angiogenesis., Qing Xu, Ling-Zhi Liu, Xu Qian, Qi Chen, Yue Jiang, Dan Li, Lihui Lai, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

MiR-145 can regulate cell apoptosis, proliferation, neural development and stem cell differentiation. Previous studies indicate that miR-145 is downregulated in human colon cancer cells. However, the molecular mechanisms of miR-145 used to regulate colon carcinogenesis and angiogenesis remain to be clarified. Here, we show that the expression of miR-145 is downregulated in colon and ovarian cancer tissues and cell lines. MiR-145 inhibits p70S6K1 post-transcriptional expression by binding to its 3'-UTR. The angiogenic factors hypoxia-inducible factor 1 (HIF-1) and vascular endothelial growth factor (VEGF), which are downstream molecules of p70S6K1, are decreased by miR-145 overexpression. P70S6K1 rescues miR-145-suppressed HIF-1 and VEGF …

Blood-Brain Barrier Abnormalities Caused By Hiv-1 Gp120: Mechanistic And Therapeutic Implications., Jean-Pierre Louboutin, David S Strayer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The blood-brain barrier (BBB) is compromised in many systemic and CNS diseases, including HIV-1 infection of the brain. We studied BBB disruption caused by HIV-1 envelope glycoprotein 120 (gp120) as a model. Exposure to gp120, whether acute [by direct intra-caudate-putamen (CP) injection] or chronic [using SV(gp120), an experimental model of ongoing production of gp120] disrupted the BBB, and led to leakage of vascular contents. Gp120 was directly toxic to brain endothelial cells. Abnormalities of the BBB reflect the activity of matrix metalloproteinases (MMPs). These target laminin and attack the tight junctions between endothelial cells and BBB basal laminae. MMP-2 and …

Graft Versus Host Disease Of The Brain Following Allogeneic Stem Cell Transplant For Myelodysplastic Syndrome, Janet Yoo, Lindsay Simon, Zi-Xuan Wang, Phd, Lawrence C. Kenyon

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Graft-versus-host disease (GVHD) is a frequent cause of morbidity and mortality following bone marrow transplantation (BMT). GVHD occurs when immune cells transplanted from a non-identical donor (the graft) recognize the transplant recipient (the host) as foreign, thereby initiating an immune reaction that causes disease in the transplant recipient. GVHD, which can present either acutely or chronically, typically involves the skin, gastrointestinal tract, and liver. In contrast, GVHD involving other organs such as the heart and kidney is highly uncommon and involvement of the central nervous system has only very rarely been described in the literature. We report an unusual case …

Knockdown Of Ki-67 By Dicer-Substrate Small Interfering Rna Sensitizes Bladder Cancer Cells To Curcumin-Induced Tumor Inhibition., Sivakamasundari Pichu, Swapna Krishnamoorthy, Andrei Shishkov, Bi Zhang, Peter Mccue, Biddanda C Ponnappa

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Transitional cell carcinoma (TCC) of the urinary bladder is the most common cancer of the urinary tract. Most of the TCC cases are of the superficial type and are treated with transurethral resection (TUR). However, the recurrence rate is high and the current treatments have the drawback of inducing strong systemic toxicity or cause painful cystitis. Therefore, it would be of therapeutic value to develop novel concepts and identify novel drugs for the treatment of bladder cancer. Ki-67 is a large nucleolar phosphoprotein whose expression is tightly linked to cell proliferation, and curcumin, a phytochemical derived from the rhizome Curcuma …

Decorin Protein Core Affects The Global Gene Expression Profile Of The Tumor Microenvironment In A Triple-Negative Orthotopic Breast Carcinoma Xenograft Model., Simone Buraschi, Thomas Neill, Rick T Owens, Leonardo A Iniguez, George Purkins, Rajanikanth Vadigepalli, Barry Evans, Liliana Schaefer, Stephen C Peiper, Zi-Xuan Wang, Renato V Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin, a member of the small leucine-rich proteoglycan gene family, exists and functions wholly within the tumor microenvironment to suppress tumorigenesis by directly targeting and antagonizing multiple receptor tyrosine kinases, such as the EGFR and Met. This leads to potent and sustained signal attenuation, growth arrest, and angiostasis. We thus sought to evaluate the tumoricidal benefits of systemic decorin on a triple-negative orthotopic breast carcinoma xenograft model. To this end, we employed a novel high-density mixed expression array capable of differentiating and simultaneously measuring gene signatures of both Mus musculus (stromal) and Homo sapiens (epithelial) tissue origins. We found that …

Kaempferol Nanoparticles Achieve Strong And Selective Inhibition Of Ovarian Cancer Cell Viability., Haitao Luo, Bingbing Jiang, Bingyun Li, Zhaoliang Li, Bing-Hua Jiang, Yi Charlie Chen

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Ovarian cancer is one of the leading causes of cancer death for women throughout the Western world. Kaempferol, a natural flavonoid, has shown promise in the chemoprevention of ovarian cancer. A common concern about using dietary supplements for chemoprevention is their bioavailability. Nanoparticles have shown promise in increasing the bioavailability of some chemicals. Here we developed five different types of nanoparticles incorporating kaempferol and tested their efficacy in the inhibition of viability of cancerous and normal ovarian cells. We found that positively charged nanoparticle formulations did not lead to a significant reduction in cancer cell viability, whereas nonionic polymeric nanoparticles …

Temporal Changes In Innate Immune Signals In A Rat Model Of Alcohol Withdrawal In Emotional And Cardiorespiratory Homeostatic Nuclei., Kate Freeman, Anthony Brureau, Rajanikanth Vadigepalli, Mary M Staehle, Melanie M Brureau, Gregory E Gonye, Jan B Hoek, D Craig Hooper, James S Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Chronic alcohol use changes the brain's inflammatory state. However, there is little work examining the progression of the cytokine response during alcohol withdrawal, a period of profound autonomic and emotional upset. This study examines the inflammatory response in the central nucleus of the amygdala (CeA) and dorsal vagal complex (DVC), brain regions neuroanatomically associated with affective and cardiorespiratory regulation in an in vivo rat model of withdrawal following a single chronic exposure.

METHODS: For qRT-PCR studies, we measured the expression of TNF-α, NOS-2, Ccl2 (MCP-1), MHC II invariant chain CD74, and the TNF receptor Tnfrsf1a in CeA and DVC …

Emergence Of Bimodal Cell Population Responses From The Interplay Between Analog Single-Cell Signaling And Protein Expression Noise., Marc R Birtwistle, Jens Rauch, Anatoly Kiyatkin, Edita Aksamitiene, Maciej Dobrzyński, Jan B. Hoek, Walter Kolch, Babatunde A Ogunnaike, Boris N Kholodenko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Cell-to-cell variability in protein expression can be large, and its propagation through signaling networks affects biological outcomes. Here, we apply deterministic and probabilistic models and biochemical measurements to study how network topologies and cell-to-cell protein abundance variations interact to shape signaling responses.

RESULTS: We observe bimodal distributions of extracellular signal-regulated kinase (ERK) responses to epidermal growth factor (EGF) stimulation, which are generally thought to indicate bistable or ultrasensitive signaling behavior in single cells. Surprisingly, we find that a simple MAPK/ERK-cascade model with negative feedback that displays graded, analog ERK responses at a single cell level can explain the experimentally …

Integrative Gene Regulatory Network Analysis Reveals Light-Induced Regional Gene Expression Phase Shift Programs In The Mouse Suprachiasmatic Nucleus., Haisun Zhu, Rajanikanth Vadigepalli, Rachel Rafferty, Gregory E Gonye, David R Weaver, James S Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

We use the multigenic pattern of gene expression across suprachiasmatic nuclei (SCN) regions and time to understand the dynamics within the SCN in response to a circadian phase-resetting light pulse. Global gene expression studies of the SCN indicate that circadian functions like phase resetting are complex multigenic processes. While the molecular dynamics of phase resetting are not well understood, it is clear they involve a "functional gene expression program", e.g., the coordinated behavior of functionally related genes in space and time. In the present study we selected a set of 89 of these functionally related genes in order to further …

Cns Recruitment Of Cd8+ T Lymphocytes Specific For A Peripheral Virus Infection Triggers Neuropathogenesis During Polymicrobial Challenge., Christine M Matullo, Kevin J O'Regan, Mark Curtis, Glenn F Rall

Department of Microbiology and Immunology Faculty Papers

Although viruses have been implicated in central nervous system (CNS) diseases of unknown etiology, including multiple sclerosis and amyotrophic lateral sclerosis, the reproducible identification of viral triggers in such diseases has been largely unsuccessful. Here, we explore the hypothesis that viruses need not replicate in the tissue in which they cause disease; specifically, that a peripheral infection might trigger CNS pathology. To test this idea, we utilized a transgenic mouse model in which we found that immune cells responding to a peripheral infection are recruited to the CNS, where they trigger neurological damage. In this model, mice are infected with …

Mutant Tdp-43 In Motor Neurons Promotes The Onset And Progression Of Als In Rats, Cao Huang, Jianbin Tong, Fangfang Bi, Hongxia Zhou, Xu-Gang Xia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Amyotrophic lateral sclerosis (ALS) is characterized by progressive motor neuron degeneration, which ultimately leads to paralysis and death. Mutation of TAR DNA binding protein 43 (TDP-43) has been linked to the development of an inherited form of ALS. Existing TDP-43 transgenic animals develop a limited loss of motor neurons and therefore do not faithfully reproduce the core phenotype of ALS. Here, we report the creation of multiple lines of transgenic rats in which expression of ALS-associated mutant human TDP-43 is restricted to either motor neurons or other types of neurons and skeletal muscle and can be switched on and off. …

The Role Of Receptor Tyrosine Kinase Axl In Pancreatic Ductal Adenocarcinoma And Its Regulation By Hematopoietic Progenitor Kinase 1, Xianzhou Song

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDA) is one of the most aggressive malignancies with less than 5% of five year survival rate. New molecular markers and new therapeutic targets are urgently needed for patients with PDA. Oncogenic receptor tyrosine kinase Axl has been reported to be overexpressed in many types of human malignancies, including diffuse glioma, melanoma, osteosarcoma, and carcinomas of lung, colon, prostate, breast, ovary, esophagus, stomach, and kidney. However, the expression and functions of Axl in PDA are unclear. We hypothesized that Axl contributes to the development and progression of PDA. We examined Axl expression in 54 human PDA samples …

Switches, Excitable Responses And Oscillations In The Ring1b/Bmi1 Ubiquitination System., Lan K Nguyen, Javier Muñoz-García, Helene Maccario, Aaron Ciechanover, Walter Kolch, Boris N Kholodenko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

In an active, self-ubiquitinated state, the Ring1B ligase monoubiquitinates histone H2A playing a critical role in Polycomb-mediated gene silencing. Following ubiquitination by external ligases, Ring1B is targeted for proteosomal degradation. Using biochemical data and computational modeling, we show that the Ring1B ligase can exhibit abrupt switches, overshoot transitions and self-perpetuating oscillations between its distinct ubiquitination and activity states. These different Ring1B states display canonical or multiply branched, atypical polyubiquitin chains and involve association with the Polycomb-group protein Bmi1. Bistable switches and oscillations may lead to all-or-none histone H2A monoubiquitination rates and result in discrete periods of gene (in)activity. Switches, overshoots …